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991.
Captive and wild African elephants frequently suffer tusk fractures. Several institutions shorten the tusks of captive elephants to reduce fractures and injury as a result of behaviour within enclosures. Fracturing or coronal amputations that expose pulp lead to pain for the elephant. Estimating coronal pulp lengths may thus help to minimise the risk of pulp exposure during amputations. We aimed to determine the length of the pulp beyond the lip margin from an external tusk characteristic. Tusks collected from elephants in Namibia and the Kruger National Park had similar morphological relationships. This statistical property allowed us to correct for missing data in our data sets. Pulp volume and pulp length correlated with tusk circumference at the lip. Even so, the circumference at the lip could not predict the length of the pulp in the crown external to the lip. Our findings suggest that tusks, irrespective of sex or age, amputated further than 300 mm from the lip should not expose pulp.  相似文献   
992.
Thoracoscopic biopsies were taken from four dogs with lung tumours using a Roeder's loop. A Roeder's loop is used to collect pulmonary tissue samples for histopathological analyses. In all the animals tissue biopsy using a Roeder's loop enabled to collect a relatively large specimen of the lung tumor tissue.  相似文献   
993.
The aim of the study was to investigate the effects of supplementation of a microencapsulated blend of tributyrin and lactitol (TL) to a standard European (EU) diet without antibiotic growth promoters on intestinal metabolism and mucosa development of weaned piglets and to compare it with a standard US diet containing animal proteins, zinc oxide, copper sulfate, and carbadox. Ninety piglets weaned at 21 d were divided into 3 dietary groups consisting of 5 replicates each: 1) US diet supplemented with 55 mg/kg of carbadox, and 2.5% each of plasma proteins and spray-dried blood cells in the first phase, 3,055 mg/kg of Zn in the first and second phases, and 180 mg/kg of Cu in the third phase; 2) EU diet based on vegetable proteins and no antibiotics; and 3) the same EU diet supplemented with 3,000 mg/kg of microencapsulated TL. The study was divided into 3 phases: 0 to 7, 8 to 21, and 22 to 35 d. On d 7, 21, and 35, animals were weighed, and feed consumption and efficiency were determined. On d 14 and 35, one pig per pen was killed, and the intestinal contents and mucosa from the proximal, middle, distal jejunum and the ileum were sampled. Intestinal wall sections were fixed for histological analysis, and intestinal content was used for VFA, ammonia, and polyamine analysis. Throughout the study (d 0 to 35), the US diet had greater ADG and ADFI than the EU diet (P < 0.05). The EU diet supplemented with TL tended to have 11% greater ADG (P = 0.17). Feeding the EU diet caused a reduction in proximal and middle jejunum villi length by 10% (P < 0.05) and an increase in crypt size in proximal jejunum (P < 0.05) compared with the US diet, probably due to an increased rate of cell loss and crypt cell production. The TL supplementation resulted in longer villi along the jejunum and less deep crypts in the proximal jejunum (+15.9 and -8.9%, respectively; P < 0.05) than the unsupplemented EU diet. The TL diet increased the concentrations of cadaverine and putrescine in the small intestine (P < 0.05) and seemed to increase cadaverine, histamine, putrescine, and spermine in the large intestine by 1.5- to 10-fold compared with the US or EU diet. In conclusion, although the US diet had a greater effect on growth performance and mucosal trophic status than the EU diets, the supplementation with slowly released TL seemed to be an effective tool to partially overcome the adverse effects of vegetable protein diets.  相似文献   
994.
Concern over the environmental effect of P excretion from pig production has led to reduced dietary P supplementation. To examine how genetics influence P utilization, 94 gilts sired by 2 genetic lines (PIC337 and PIC280) were housed individually and fed either a P-adequate diet (PA) or a 20% P-deficient diet (PD) for 14 wk. Initially and monthly, blood samples were collected and BW recorded after an overnight fast. Growth performance and plasma indicators of P status were determined monthly. At the end of the trial, carcass traits, meat quality, bone strength, and ash percentage were determined. Pigs fed the PD diet had decreased (P < 0.05) plasma P concentrations and poorer G:F (P < 0.05) over the length of the trial. After 4 wk on trial, pigs fed the PD diet had increased (P < 0.05) plasma 1,25(OH)(2)D(3) and decreased (P < 0.05) plasma parathyroid hormone compared with those fed the PA diet. At the end of the trial, pigs fed the PD diet had decreased (P < 0.05) BW, HCW, and percentage fat-free lean and tended to have decreased LM area (P = 0.06) and marbling (P = 0.09) and greater (P = 0.12) 10th-rib backfat than pigs fed the PA diet. Additionally, animals fed the PD diet had weaker bones and also decreased (P < 0.05) ash percentage and increased (P < 0.05) concentrations of 1alpha-hydroxylase and parathyroid hormone receptor mRNA in kidney tissue. Regardless of dietary treatment, PIC337-sired pigs consumed more feed and gained more BW than their PIC280-sired counterparts (P < 0.05) during the study. The PIC337-sired pigs also had greater (P < 0.05) HCW, larger (P < 0.01) LM area, and tended to have (P = 0.07) greater dressing percentage. Meat from the PIC337-sired pigs also tended to have greater (P = 0.12) concentrations of lactate but decreased (P = 0.07) concentrations of total glucose units 24 h postslaughter. Although plasma 1,25(OH)(2)D(3) concentrations were elevated (P < 0.05) in all the animals fed the PD diet, this elevation due to P deficiency tended (P = 0.09) to be greater in the PIC337-sired pigs after 12 wk on the treatment. The PIC337-sired pigs had stronger (P < 0.01) bones with greater ash percentage than the PIC280-sired pigs. The difference in the strength of the radii between the PIC337-sired pigs fed the PA and PD diets was greater than their PIC280-sired counterparts, which resulted in sire line x treatment interactions (P < 0.05). These data indicate differing mechanisms of P utilization between these genetic lines. Elucidating these mechanisms may lead to strategies to increase efficiency of growth in a more environmentally friendly manner.  相似文献   
995.
OBJECTIVE: To determine pharmacokinetics of buprenorphine in dogs after i.v. administration. ANIMALS: 6 healthy adult dogs. PROCEDURES: 6 dogs received buprenorphine at 0.015 mg/kg, i.v. Blood samples were collected at time 0 prior to drug administration and at 2, 5, 10, 15, 20, 30, 40, 60, 90, 120, 180, 240, 360, 540, 720, 1,080, and 1,440 minutes after drug administration. Serum buprenorphine concentrations were determined by use of double-antibody radioimmunoassay. Data were subjected to noncompartmental analysis with area under the time-concentration curve to infinity (AUC) and area under the first moment curve calculated to infinity by use of a log-linear trapezoidal model. Other kinetic variables included terminal rate constant (k(el)) and elimination half-life (t(1/2)), plasma clearance (Cl), volume of distribution at steady state (Vd(ss)), and mean residence time (MRT). Time to maximal concentration (T(max)) and maximal serum concentration (C(max)) were measured. RESULTS: Median (range) values for T(max) and MRT were 2 minutes (2 to 5 minutes) and 264 minutes (199 to 600 minutes), respectively. Harmonic mean and pseudo SD for t(1/2) were 270+/-130 minutes; mean +/- SD values for remaining pharmacokinetic variables were as follows: C(max), 14+/-2.6 ng/mL; AUC, 3,082+/-1,047 ng x min/mL; Vd(ss), 1.59+/-0.285 L/kg; Cl, 5.4+/-1.9 mL/min/kg; and, k(el), 0.0026+/-0.0,012. CONCLUSIONS AND CLINICAL RELEVANCE: Pharmacokinetic variables of buprenorphine reported here differed from those previously reported for dogs. Wide variations in individual t(1/2) values suggested that dosing intervals be based on assessment of pain status rather than prescribed dosing intervals.  相似文献   
996.
In this study, we injected morphine sulfate IP into rainbow trout and measured the concentration of morphine and all potential metabolites in plasma using LC-MS/MS at a series of times after the injection. The pharmacokinetics of morphine were similar to those previously reported for seawater-acclimated rainbow trout, i.e. they were about one order of magnitude slower than in similarly sized mammals. The only metabolite of morphine present in the plasma was morphine-3-β- d -glucuronide (M3G); morphine-6-β- d -glucuronide (M6G) was not detected. M3G gradually increased after the morphine injection, peaked about 2 days later, then gradually decreased. In mammals, M3G plasma levels exceed morphine levels extremely rapidly, i.e. in less than an hour, regardless of dose, route of administration, or species. In trout, it took 2 days for M3G levels to exceed morphine levels. This is the first study of the metabolites of morphine in any ectotherm. We conclude that trout can metabolize morphine, but at a rate much slower than in mammals.  相似文献   
997.
1. Water used in a modern poultry processing line was tested from October 2005 to June 2006 to determine the level of bacteria in an abattoir in Germany.

2. A total of 420 water samples were taken from 14 processing sites (PSs), at 10 times, and from three different hours of the working shift at three sampling hours (SHs) at 5:00 a.m. (SH 1), 9:00 a.m. (SH 2) and 12:00 a.m. (SH 3). Each sample was assessed for the aerobic plate count (APC) and the prevalence of Salmonella, Campylobacter, Listeria and Yersinia over 30 sampling weeks. The APC numbers of each PS from three SHs were compared, and the prevalence of Salmonella, Campylobacter, Listeria and Yersinia from each PS of three SHs was determined as well as change from the initial PS to the end of the processing line.

3. A total of 46 water samples were positive for Salmonella, 120 positive for Campylobacter and 4 positive for Listeria. None of the water samples was found to be positive for Yersinia. During the course of the day, the APC increased. Salmonella was mostly found during SH 1 (5 a.m.) in water from all PSs. A high number of Campylobacter were observed at SH 2 (9 a.m.) and SH 3 (12 a.m.) from all PSs.

4. The results show that water, which is still used in substantial amounts in present poultry processing technology, can serve as a carrier for Salmonella and Campylobacter.

5. The findings indicate that birds might progressively contaminate the equipment and become contaminated via the same equipment, that water at every processing position of the line constitutes a risk and that more attention should be paid to effective water management in the processing plan.  相似文献   

998.
The genetic relationship among individuals at one locus is characterized by nine coefficients of identity. The coefficients of inbreeding, coancestry and dominance (or fraternity) are just linear functions of them. Here, it is shown how they can be estimated using biallelic and triallelic markers using the method of moments, and comparisons are made with other methods based on molecular coancestry or molecular covariance. It is concluded that in the general case of dominance and inbreeding with biallelic markers, only the coefficients of inbreeding and coancestry can be estimated, but neither the single coefficients of identity nor the coefficient of dominance can be estimated. More than two alleles are required for a full estimation as illustrated with the triallelic situation.  相似文献   
999.
Diet plays an important role in maintaining rabbit health. Feeding an incorrect diet, particularly a low fibre diet, has been linked with digestive, dental and urinary tract disease. However, food intake and dietary requirements have been poorly studied in pet rabbits. This study assessed the effects of two commonly fed pet rabbit diets [extruded nuggets with hay (EH) and muesli with hay (MH)] alongside hay only (HO) and muesli only (MO) on food and water intake in 32 Dutch rabbits. Dry matter (DM) intake was greater in the HO group and lower in the MO group than in the EH and MH groups (p < 0.001). The portion of the diet made of hay was greater in the EH group than in the MH group (p < 0.001). Water intake was positively correlated with DM intake and was greatest in the HO group (p < 0.001). Selective feeding occurred in all rabbit groups fed muesli, whether or not hay was also available. Pellets were rejected, and grains and extrudates selected. The presence of selective feeding in all rabbits fed muesli leads to the consumption of an unbalanced diet. In addition, hay intake and water intake were lower when muesli was fed. Conclusions drawn from this study are based on general recommendations for pet rabbits, and clinical disease may have developed by feeding the study diets over a longer time period, as many diet‐related conditions typically present in older rabbits. However, the study demonstrates that the feeding of muesli diets cannot be recommended.  相似文献   
1000.
Seven related young pugs were diagnosed with cervical spinal intradural arachnoid cysts by magnetic resonance imaging (n = 6) and myelography (n = 1). All dogs were presented with skin abrasions on their thoracic limbs and non‐painful neurological deficits, indicating a C1‐T2 myelopathy. In all six dogs examined by magnetic resonance imaging not only the spinal arachnoid cyst but also a concomitant, most likely secondary, syringohydromyelia was confirmed. Pedigree analysis suggested a genetic predisposition for spinal arachnoid cysts in this family of pugs. Generalised proprioceptive deficits more pronounced in the thoracic limbs suggesting a focal cervical spinal cord lesion, with concomitant skin abrasions on the dorsal aspect of the thoracic limbs in a young pug, should alert veterinarians to the possibility of cervical spinal arachnoid cysts.  相似文献   
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